Silencer.



J. WEIL.

SILENCER.

APPLICATION FILED NOV- il. 1914.

1,187,581. Patented June 20,1916.

wmmvwfdw STATES PATENTOFFIVCE.

JOHN F MANSFIELD, OHIO.

sInENcER. I

Patented June 20, 1916.

1,1 7,5 1. Specification of Letters Patent.

I Application filed November 11, 1914. Serial No. 871,493.

To all whom it may concern: a 1

Be it known that I, JoHN WEIL, a citizen of the United States of America, residing at Mansfield, in the county of Richland and State of Ohio, have invented certain new and useful Improvements in Silencers, of which" the following is a specification.

The present invention relates to silencers, and more particularly to that class of silencers which are used to muflle the exhaust from internal combustion motors.

It is well known that there is considerable noise occasioned by the exhaust from the explosion in ordinary internal combustion motors, and this is especially true in those high speed motors ordinarily employed for the propulsion of motor vehicles. In order to reduce this noise means have been heretofore provided for muffling the exhaust gases, the means ordinarily employed comprising a hollow shell on the interior of which is arranged a number of baflle plates by means of which the force of the spent exhaust gases is retarded before being admitted to the atmosphere. These means usually effectively deaden the noise, but at the same time the power developed by the motor is correspondingly re duced, due to the choking or back-pressure effect of these spent exhaust gases, and in order to overcome this reduction in power a further means is usually employed whereby the muffler is manually cut out and the spent gases allowed to exhaust direct to atmosphere whenever it is desired to secure the full power developed by the motor, for instance when climbing hills, etc. In this case, however, the noise from the spent ex haust gases is not reduced. It will there'- fore be seen that with these appliances it is impossible to secure the full power developed by the motor without the objectionable noise caused by exhausting the spent gases direct to atmosphere.

The principal object of the present invention is, therefore, to provide a silencer for internal combustion motors whereby the maximum power developed by the motor will be effective, and at the same time the noise caused by the ejection of the spent exhaust gases will be reduced to an unobjectionable degree.

Another object is to provide a silencer of the character indicated that will not necessitate the use of a manually operated,

which will be simple and inexpensive in construction, and reliable and efficient in operation.

- These and other objects are accomplished by the construction and arrangement of parts hereinafter fully described, and shown in the accompanying drawings, in which:

Figure 1 is a longitudinal sectional elevation of a silencer embodying my invention, and F ig. 2 is a longitudinal sectional eleva tion of the same, in perspective, with the inner casing in its outermost position.

Referring more particularly to the drawing, reference numeral 1 indicates generally a cylindrical shell or casing I preferably formed with the reduced portion 2 projecting from one end thereof, thus providing an expansion chamber 3. A boss or projection 4 is internally threaded to engage the external thread on the exhaust conductor or pipe 5 which conducts the spent exhaust gases from the'motor. While I have shown a threaded connection as the preferred methodof attaching my improved silencer to the. exhaust pipe, yet it will be understood that any other suitable means desired may be employed for this purpose. I also provide an inlet port 6 leading from the exhaust pipe into the expansion chamber 3, the area of this port being proportioned to the area of the exhaust pipe.

The outer shell 1 is preferably constructed in two parts, the portion 7 being adapted to telescope snugly over the portion 8. Two sets of outstanding lugs 9 and 10- are provided on the outer periphery of the portions 7 and 8, respectively, each pair of lugs?!) and 10 being properly alined with respect to each other. The lugs 9 have one end of the studs or bolts 11 securely fastened on the inner periphery of the outer casing and the outer periphery of the inner casing respectively, serving as bearings to keep the casings in proper alinement with respect to each other. Packing rings 17 may berovided if desired to prevent the gases f om escaping into the annular spring chamber 18. A compression spring 19 encircles the inner casing 14 and has one .end engaging the circular shoulder in the outer casing, and the other end engaging the annular flange 16 on the inner casing. It will thus be seen that the spring 19 normally tends to force the inner casing to the forward end of its travel and against the stop shoulder 21 in the outer casing. It will also be observed that by varying the length of the outer casing by means of the adjusting screws 11 and nuts 13, as hereinbefore described, the tension of the spring 19 can be adjusted as desired.

The inner casing 14 is provided with the reduced neck portion 22 which is somewhat smaller than the reduced portion 2. The neck portion 22 extends into the chamber 3 and is adapted to partially close the inlet port 6 when in its normal position. The degree to which the inlet port 6 is closed when the-inner casing is in its normal position, as shown in Fig. 1, depends upon the size of the motor and the capacity of the exhaust pipe with which the silencer is used, and may be varied to suit individual conditions, this being accomplished either by entirely closing the end of the neck portion 22 and providing a suitable aperture or clearance at 23, or by providing a suitable port 24 in the end of the neck portion 22 and allowing the said end to engage or seat against the seating ring 25, or by providing both the port 24 and the aperture 23 (this being the preferable arran ement), in which case the combined area 0 the port 24 and aperture 23 should be just sufiicient to permit the spent exhaust gases from the motor to freely pass through these ports when the motor is .running idle, that is, when the motor is running but not" pulling a load. The inner casing 14 is also provided with the ports 26 and 27, and the baflles 28, the number, size and arrangement of these ports and bafiles being proportioned to suit the particular conditions under which the silencer is'designed to work.

The outer end of the casing 1 is provided with the outlet port 29, and I also preferably provide an auxiliary outlet port 30 which is normally closed by the spring-held valve 31. Any desired means may be employed for retaining the valve 31 in position, such for instance as the spring 32 which engages a suitable aperture 33 in the valve and is supported by the screw 34 which is screw-threaded into the. casing at 35. An extensionarm 36 is secured to the inner casing 14, and is properly alined with the port 30 so that as the casing 14 nears the outer end of its travel the arm 36 will actuate the valve 31, thatis, raise it from its seat and thereby open the auxiliary port 30 as shown clearly in Fig. 2.

From the foregoing it will be understood that when the motor is running idle my improved silencer' mufiles the noise from the spent exhaust gases in a similar manner to the ordinary and well known mufiler. When the speed of the motor is increased or when the motor is pulling a load the increased pressure of the spent exhaust gases against the face 37 of the neck portion 22 tends to move the inner casing 14 toward its outer position against the tension of the spring 19, because the capacity of the ports 23 and 24 is not sufiicient to permit the gases to pass freely under these conditions. It being understood of course, that the pressure of the exhaust gases is proportionate to the speed Or load of the motor. As the neck portion 22 of the inner casing 14 recedes from the seating ring 25 of the port 6 the volume of the chamber 3 is increased andthe exhaust gases are free to expand upon entering this chamber. The gases then pass from the chamber 3 through the ports 26 and 27 into the interior of the casing 14, as indicated by thearrows in Fig. 1, where they come in contact with thebafiles 28, and the force of the gases is thereby impeded and further expansion takes place. The spent gases finally pass to atmosphere through the outlet port 29, and also through the auxiliary port 30, provided the inner casing 14 has traveled near enough to its outermost position to cause the arm 36 to. raise the valve 31 from its seat. The gases pass to atmosphere under practically no pressure, due to the previous expansion, the noise being therefore effectively deadened, and at the same time the power developed by the motor has not been affected.

While I have shown and described the preferred embodiment of my invention, yet' it will be understood that many alterations may be made in. the details of construction without departing from the spirit and scope of my invention, and .I do not therefore wish to be limited to the exact structure shown.

What I claim and desire to secure by Letters Patent is 1. A silencer comprising an exhaust pipe, a two-part outer casing secured thereto, an innercasing slidably arranged in said outer casing and having one end partially closed, a spring encircling said inner casing and tending to normally hold the closed end of said' inner casing against the end of said exhaust pipe, and means for adjusting the two-part outer casing substantially as described. v

2. A silencer comprising an exhaust pipe, an outer casing secured thereto, an inner casing slidably arranged in said outer casing and having one end partially closed, a spring encircling said inner casing and tending to normally hold the closed end of said pipe, and means for adjusting the tension of said spring, substantially as described.

3. A silencer comprising an outer casing rovide with an ex ansion chamber an in-.

"for adjusting the tension of said spring, substantially as described. V

4. A silencer comprising. an outer casing provided withan inlet port at one end and an outlet port at the other end, an inner cas ing slidably arranged in said outer casing and having one end partially closed and the other end open, a spring encircling said inner casing and tending normally to cause the closed end of said inner casing to close the said inlet port, and means for adjusting the tension of said spring, substantially as described.

5. A silencer comprising an outer casing provided with an inlet port and an expansion chamber atone end thereof, an inner casing slidably arranged in said outer casing, said inner casing having a reduced neck portion normally extending into said ex ansion chamber, a spring encircling sai inner casing and tending normally to causethe end of said neck portion to partially close the said inlet port, and means for adjusting the tension of said spring, substantially as described.

6. A silencer comprising an exhaust pipe, an outer casing having one end secured to said exhaust pipe and provided with a chamber adjacent the end of said exhaust pipe, an inner casing slidably arranged in said outer casing, the inner end of said inner casing being partially closed and provided with a port, thebther end being open, a spring encircling said inner casing and tending to normally hold the closed end of said inner casing against the end of said exhaust pipe and means for adjusting the tension of said spring, substantially as de-' scribed.

7. A silencer comprising an exhaust pipe, an outer casing having one end secured to said exhaust pipe and provided with a chamber adjacent the end of saidexhaust pipe, the other end of said'outer casingbeing provided with an exhaust port and an auxiliary exhaust port, a spring held valve adapted to normally close the auxiliary exhaust port, an inner casing slidably arranged in saidouter casing, the inner end of said inner casing being yieldingly secured against the end of said exhaust pipe, and means on said inner casing for opening the said spring held valve when the said inner casing is in. its outermost position, substantially as described.

8. A silencer comprising an outer casing provided with an inlet port at one end, and an outlet port and an auxiliary port at the other end, a valve secured to said outer casing tending normally to close said auxiliary port, an inner casing slidably arranged in said outer casing oneend of said inner casing being partially closed and the other end being open, a spring encircling said inner casing and tending normally to cause the closed end of said inner casing to close the said inlet port, means for adjusting the ten sion of said spring, and means for actuating said valve to open said auxiliary port when the said inner casing is in its outermost pdsition, substantlally as described.

9. Avsilencer comprising an outer casing provided with an inlet port and an expansion chamber at one end thereof, and an outlet port and an auxiliary port at the other end thereof, a valve secured to said outer casing adapted to close said auxiliary port, an inner casing slidably arranged in said outer casing, a reduced neck portion secured to said inner casing normally extending into said expansion chamber and adapted to partially close said inlet port, the said neck portion being provided with ports on the face and periphery thereof, baffles suitably arranged within said inner casing, annular rings providing circumferentialshoulders on the outer and inner casings, the said shoulders being spaced apart,packing rings in said annular rings, a compression spring seating between said shoulders, means for adjusting the tension of saidspring, and means for actuat ing said valve to open said auxiliary port'when the inner casing is in its outermost position, substantially as described.

Y 10. In an internal combustion motor silencer, the combination with the exhaust pipe, of a two-part outer casing secured thereto, an inner casing having one end closed and the other end open, slidably arranged in said outer casing, a spring tending normally to hold the closed end of said' inner casin against the end of said exhaust pipe, suitalily alined lugs on each of the two parts of the said outer casing, and bolts op- 'eratively arranged in said lugs whereby to vadjust the tension of said spr1ng,'substantially as described.

In testimony -whereofI afiix my signature in presence of two vn'tnesses. JOHN WEIL.

(Witnesses; f a

G. W SrAmR, JNO. L; YOUNG. 

